Flush pin gauge



July 11, 1950 W, G, PRlNCE 2,514,794

FLUSH PIN GAUGE Filed oct. '7, 1947 f JNVENTOR. :E Z 57, 4 Wes/eg 6. ,Dr/'nce 757/wqmwz Him/Mam Patented July 11, 17950 UNITED STATES ATENT' OFFICE i 2,514,794

FLUSH PIN GAUGE Wesley G. Prince, Menominee, Mich. l

Application October 7, 1947, Serial No. 778,511

This inventionrelates to a flush pin gauge, and has Aas its primary object the provision of an improved gauge adapted `for the checking of the depths of countersinks, counterbores, drilled holes,

slots, etc. s

A further object of the inventionis the provision ofa flush pin gauge .provided with a spherical variation in depth of the countersink limited by the tolerance of the job maybe accurately measured, while too deep or too shallow a countersink will be immediately detected by use of the gauge. Y

Still another object ofthe invention is the provision of the device of this character providing cylindrical line contact about the periphery of a countersink, or bore, or the like, in such manner as to provide extremely accurate measurement of the depth thereof, such measurement not being affected by chips,v shavings, or the like, which now 4customarily affect the angularly-ground shafts of conventional flush `pin gauges.

Still other objects will, in part, be obvious and in` part .be. pointed out as the description of the invention proceeds, and shown in the accompanying`',drawir1g,` wherein there is disclosed a preferred embodiment of the inventive concept.

- Ivnlthe drawing:

Figure 1 is a vertical, longitudinal sectional view taken substantially along the center-line of one form of gauge embodying features of the instant invention, certain interior portions thereof being shown in plan, the view being taken substantially along the line I-I of Figure 2.

Figure 2 is a top plan view of the device. Figure 3 is a bottom plan view'of the device.

Figures 4 and 5 are side elevational Views of thev assembled gauge shown in association with a countersink, the latter being sectioned, in two diierent positions of adjustment.

Similar reference characters refer to similar parts throughout the several views of the drawings.

Referring to the drawings in detail, the device of the instant invention comprises an elongated,

cylindrical body I0, having flat, substantially parallel ends and a longitudinal bore I I extending s claims. (C1. 3341691 therethrough, substantially parallel to said endsy A Icounterbore I2 is provided in said body at its base end substantially concentric with said bore. l The lower portionof the body I0 is tapered as at Q I3, forming a conicalfrustrum, to facilitate accuracyof inserton'o the gauge into a countersinkor counter-bore. Positioned Within the bore` II is'a cylindrical plunger I4, provided with an l externally screw-threaded portion I5 of reduced diameter providing an annular shoulder I 8 at the inner end of thescrew-threaded portion. A gauge ball 2I has an internally screw-threaded sleeve 2 2 I integral therewith intol which the reducedllor-A tion I5 of plunger' I4 is threaded. The end of sleeve 22 opposite ball 2| provides an annular shoulder i9 spaced from and opposed to shoulder `Aset screw I6 having a reduced, cylindrical* inner end portion is threadedthrough anintejrnally screw-threaded, radially-extending aper-y -ture Il inbody I so that its reduced inner end is disposed between shoulders I8 and I9 to maintain body Ill, plunger I4 and gauge ball 2| against separation` With the. above-disclosed arrangement the4 gauge ball may beadjustably threaded onto the cylindrical member or plunger I4. It is secured in adjusted position relative to the plunger by a locking plug 2t threaded in the sleeve 22 at the end of plunger I4- received in the sleeve and bearing against the plunger to lock the plunger and sleeve against relative rotation. This plug 20 is provided `'in gtheface thereof facing ball ZI with a hexagonal recess 26 which receives a conventional heXagonally-shaped wrench for turning the plug.

The ball 2I is provided with an aperture or hole 2l opening at the bottom center thereof and extending coaxially with `the longitudinal axis of,

ball2I and ,sleeve 2 2 through which hole the wrench may bev inserted to turn the locking plug Ellwhen it yis 4desired to adjust the gauge ball relative to thestem I4.

The `upper end ff plunger a .transve rs e groove 23, deiining two at upper surfaces 2d and 25 0f relatively `diierent heights,l

I4 is provided with the countersink, or other depth being measured, is`

within permissible limits. Obviously, when the surface 25 is above the surl face 33 the countersink is too shallow, and equallyobviously, whenthe surface 24 is below the surface 33 the countersink is too depn A From the foregoing it will now be seen that.. there is herein provided `Van improved flush pin gauge which accomplishes all lthe objects of .this invention, which may-be re-utilized successively forja plurality oi various types of jobs merelyl bg'the substitution of aball member 2| of a size in accordance with the, requirement of the countersinkor bore being measured, and which accomplishes all the objects of this invention, and others, including many advantages of great practical utility and commercial importance. vis-various embodiments may be made in this inventive concept, and'various modications may be' made in the embodiment hereinbefore shown anddescribed, it isto be understood that all mat;

terj'herein is to be interpreted merely as illustrativeand not in a limiting 'claim: i 1. A Vflush Apin gauge comprising an elongated substantially cylindrical body having flat, 'sub-V sense.

stantially parallel ends and abore extending@l longitudinally therethrough substantially per- Q perriiqular t0 .Said @mis Said badvhavng a 991111- teibore in'one end coaxial with saidblore, a cylin- I dricaljplunger slidable in said bore and having onn oneend stepped ,surfacesdregistrable with, the opposite end of said body for indicating the maxiu and minimum depth limits of a work piece aperture to be measured, said plunger havingan externally screw-threaded portion offreduced diamel-,er` terminating at the oppositer end of said plungena gauge ball received in said counterbore, and an internally screw-threaded sleeve joined lat *A one end to said ball and projecting therefrom,VV said sleeveA receiving said externally screw-threaded portion of said'plunger, and means in said sleeve locking said plunger in adjusted positionc'relative istrable with the opposite end of said body for indicating the maximum and minimum depth limits of a work piece aperture to be measured, said plunger having within said bore an externally screw-threaded portion of reduced diameter terminating at the opposite end 0f said plunger. a gauge ball receivable in said counterbore, an internally screw-threaded sleeve joined at one end to said ball and receiving said externally screwthreaded portion of said plunger, and means locking said plunger in adjusted position in said sleeve comprising a locking plug threaded in said sleeve atV the sleeve-received end of said plunger to bear-against said plunger and lock the same against rotationrelative to said sleeve, said plug having a non-circular, wrench-receiving recess therein and `said vball .having an aperture therethroughffor admission of a wrench of said plug recess.

uA `ilush pin gauge comprising an elongated body having iiat, substantially parallel ends and a bor'e'extending lo'r'igitudinally 'therethrough substaitially perpendicular to said ends, said body y having in one enda counterbore substantially coaxial with said bore, a` cylindrical plunge'r-slid-f able said bore and'having on one end stepped surfaces registrablewith the opposite end of said 'bdy'for'V indicating the maximum and minimum-f depth limits of a work piece aperture to be measi 4ured, a'gball receivdin said counterbore'rand adjustably secured tosaidplunger, said Aball being 1T extlnd'ible out 'of-said recess for inserticn'intoa work piece' aperture' to be measured,'said body havin'gfa radially-dispcrsed internally screw-l2 lthreaded aperture therein extendingv Vfrom-the exterioifoi" rsaid bodyinto Vsaid bore,- and means-ff releasably maintaining said body. vsaid plunger and said gauge ballin operative association corn- 'f prising means adjustably securing said ballto said plunger, a'pair orspaced-apart shoulders on said ball-and-plunger assembly Within said borefand.` a jset screw threaded through said vaperture.':and having one end disposed between said shoulders' WESLEYQPRINCE; .i

Y I u .4 "TREERENCES CITED` The following references are of record "tluie le' Ofi'this;patent;v v 

